With the advent of larger and more powerful planes circulating on airport runways and taxiways that were constructed many years ago, there is a serious safety concern regarding overhanging engines which now frequently extend well beyond the existing runway and taxiway shoulders. The new generation of aircraft presently being manufactured have very large wing spans resulting in the jet engines overlapping the existing runway and taxiway shoulders, and in many cases actually hanging over the natural grass areas bounding the runway or taxiway, thus greatly increasing the risk of damage to aircraft engines by the presence of foreign objects.
The majority of airport runway and taxiway shoulders are constructed of asphalt which may have deteriorated surfaces and edges, such as cracking and spalling. This creates a serious risk of damage to aircraft and particularly aircraft engines overhanging the airstrip shoulders caused by foreign objects such as loose pieces of asphalt and debris that could be ingested by the aircraft engines. Foreign object damage is a primary safety concern for both airport operators and aircraft manufacturers since it could have catastrophic results. In addition to foreign object damage potential, asphalt pavements require periodic maintenance and/or complete replacement which adds to the overall airport operation costs.
In order to minimize the risk of foreign object damage to aircraft engines and in order to comply with regulatory safety issues, one solution is to increase the width of existing runways and taxiways using concrete or asphalt placed over deep bases in traditional construction methods. However, the costs related to traditional construction methods and to airport operation down-time resulting from the traditional construction are very significant and in some cases not feasible.
Air fields are generally constructed in large open areas and so in addition to jet blasts and vortex shedding, they are exposed to wind storms, ice and snow storms as well as sand storms, which requires expensive maintenance of existing topsoil bounding the runways and taxiways, such as cutting, grooming, cleaning, etc., in order to ensure efficient surface drainage of water, and to avoid water ponding and possibly freezing of the surface water on the runway.
Therefore, there is a need for improvement of airport runways and taxiways, particularly the need for improvements of the extension of existing runway and taxiway shoulders.